Explanation:
The species with a positive charge over it, which means lack of electrons are called cations. Whereas the species with negative over it, meaning it has an excess of electrons with it are called anions.
From the list given the cations are
H+, Ba2+, Hg2+, Li+, Ca2+ and Fe2+
Whereas anions from the list are
O-2, Br-5, F-, S-2.
A Combination of cation and anions make an ionic compound in which cation is written first and then anion.
1/8=(1/2)^3 and the half life of radon is 3.8days
Half life is the time it takes for half of any amount of a radioactive substance to decay into something else.
Therefore for a sample of radon to decay to 1/8 of its original amount, it would take 3 x 3.8days=11.4 days
Answer:c
Explanation:because the light is hitting the Earth straight on without a slant or without all the light, it is the most direct
Dmitri Mendeleev
<span> Dmitri Mendeleev and Lothar Meyer individually came up with their own periodic law "when the elements are arranged in order of increasing atomic mass,
certain sets of properties recur periodically.</span>